Boerhaave Museum, byname of Royal Museum Of The History Of Natural And Exact Sciences, Dutch Rijksmuseum Voor De Geschiedenis Van Der Natuurwetenschappen En Van De Geneeskunde, in Leiden, Neth., museum of the history of natural sciences and one of the foremost European museums of its type. It has a fine collection of old scientific instruments. There is a collection of microscopes belonging formerly to Antonie van Leeuwenhoek (1632–1723) and thermometers from the collection of D.G. Fahrenheit (1686–1736).